A collar of this type is known by U.S. Pat. No. 4,713,863. In that collar, the fastening stud is formed on the top of a first ear, while the aperture into which that stud penetrates for the purpose of performing the fastening is formed in the top of a second ear. Each of those ears is of a generally upside-down L-shape, and they are formed by successive folds that extend transversely over the entire width of the strip. In addition, the height of the ears, as measured from the plane of the strip, is about ⅔rds of the radius of the collar. As a result, the ears are very flexible so that the collar presents relatively low overall rigidity. In addition, the large radial height of the ears can constitute a drawback for certain applications, in particular when the collar serves to clamp a rotary part because the center of gravity of the collar is far from the geometrical center of the circle that the strip of the collar forms when said collar is closed.
EP 0 846 906 discloses another collar of the above-mentioned type, in which the fastening stud is formed by a radial double fold that extends transversely over the entire width of the strip. In order to stiffen that double fold, stiffener ribs are formed at the foot of the stud. Unfortunately, the rib that is situated at the back of the stud forms a ramp that hinders bringing a clamping tool of the pliers type into engagement with the foot of the stud. The ear is of a generally upside-down L-shape, and it is formed by a succession of folds that extend transversely over the entire width of the strip. The ear is stiffened in the bend of the L-shape by a rib. That stiffening (at the foot of the stud, and in the bend of the ear) can be insufficient for certain uses. In addition, the ear and the fastening stud present radial height of the order of one half of the radius of the circle formed by the collar when said collar is closed. That very significant radial height might also shift the center of gravity away from the geometrical center of the above-mentioned circle, which poses difficulties as mentioned above when the collar serves to clamp a rotary part.